1. Field of the Invention
The present invention relates to incremental ratchet advance means especially adapted for use in an inexpensive, portable work station for manually applying a liquid solution from a hand-held liquid dispenser, such as a multiple pipette dispenser, with greatly improved accuracy to a multi-well slide or plate.
2. Background of the Invention
In many fields and most notably in the medical field, the application of liquid solution from one or more liquid applicators to a plate or slide in an accurate and convenient fashion is of great importance.
There exists, for example, fully automated devices for dispensing liquid solution from a plurality of dispensers such as pipettes, in controlled-amounts to specific locations on a plate or slide. A problem with such devices has been that they are extremely costly, frequently far beyond the means of smaller laboratories.
U.S. Pat. Nos. 4,478,094 and 5,055,263 relate to automated liquid transfer procedures. The devices described are not adapted for portable, manual operations as is the device of the present invention.
U.S. Pat. No. 4,988,618 relates to magnetic separation devices for use in immunoassay or hybridization assay procedures. The reference does not describe the portable, manually operated device of the present invention.
U.S Pat. No. 4,919,894 provides an apparatus for pipetting material in individual microwells on a micro-teter plate. The reference does not describe the apparatus of the present invention which is believed to be easier to use and more accurate.
U.S. Pat. No. 4,276,048 provides an automated device fors conducting a multiplicity of chemical reactions with micro-volumes of liquids. The reference does not show the manually operated portable apparatus of the invention.
U.S. Pat. No. 3,168,124 describes a fluid sampling apparatus which acquires a fluid sample and dispenses the sample into a container such as a test tube. The reference does not show the apparatus of the present invention.
There are many applications, especially in the medical testing area, where laboratory workers must apply a liquid solution with a hand-held liquid dispenser to a multi-well slide or plate in a convenient and accurate manner. In such applications it is important that the slide or plate be held in a steady and precise alignment, that the hand-held liquid dispenser be held steady in alignment with the slide or plate and that the liquid be dispersed accurately onto the slide or plate.
The present invention provides incremental ratchet advance means useful in a portable device which is specifically designed to assist a lab worker in the use of a hand-held liquid dispenser in the convenient and accurate application of a liquid solution onto a slide or microwell plate.